Scalable Inman Flash Replacement

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Scalable Inman Flash Replacement (sIFR) is an open sourceJavaScript and Adobe Flash dynamic web fonts implementation, enabling the replacement of text elements on HTML web pages with Flash equivalents. It was initially developed by Mike Davidson and improved by Mark Wubben. It is a scalable variety of HTML text-to-flash replacement pioneered by Shaun Inman.

Contents

Overview

CSS support in web browsers did not, at the time of sIFR's creation, allow webpages to dynamically include web fonts, so there was no guarantee that fonts specified in CSS or HTML would show as intended, as the browsing user may or may not have had the specified font installed in their system. sIFR embeds a font in a Flash element that displays the text, preempting the need for a font to have been manually pre-installed on a user's system.

A common technique is to use raster graphics to display text in a font that cannot be trusted to be available on most computers. Text created this way pixelates when scaled and cannot be partially selected. In contrast, sIFR text elements mimic normal HTML text – they are relatively resizeable and copyable.

sIFR requires JavaScript to be enabled and the Flash plugin installed in the reading browser. If either condition is not met, the reader's browser will automatically display traditional CSS based styling instead of the sIFR rendering. sIFR is not designed for body copy text as rendering greater bodies of text with Flash place formidable demands on the computer. Due to this restriction, Mike Davidson himself admitted that[1]

Although accessibility can be preserved using this technique, users should be aware that sIFR affects page loading time (from the multiple requests required for the Flash, JavaScript and CSS files used by sIFR). Also, the growing popularity of browser ad blocker plugins may decorate Flash content with a "block" button and thereby obscure the text.

Alternatives

Since the creation of sIFR, dynamic web fonts support in browsers has been renewed, with at least the latest versions of the four most popular browsers supporting them.

Facelift Image Replacement (FLIR) is a similar software to sIFR. But instead of using flash, it embeds plain images, that are generated automatically from the text on the webpage. So even if user does not have flash plugin installed, he will see the text replaced by FLIR. However, FLIR requires that the website host is capable of running PHP, and it is even less accessible than sIFR.

Cufón is an alternative that converts font paths to VML paths stored in JSON and then renders the fonts using a JavaScript rendering engine.

Trivia

The name of the original technique was derived from an anagram of the acronym for the CSS image-replacement technique it was designed to replace, Fahrner Image Replacement.